"We expect London Wasps to be very tough because they will want to go back to the Heineken Cup at all costs after having missed their campaign this season," said Nallet, who joined Racing-Metro 92 after the club won promotion to the French Top 14 earlier this year.
"They will definitely fight hard to go all the way and regain their prestige. So they certainly have really high expectations. "I played against London Wasps in previous European opening games when I was at Castres, both in 2008/09 and 2007/08, so I know a fair bit about them.
"Wasps are a great team and year after year I always feel appreciative of high-profile clubs such as them."
As for his own side and their chances of making the knockout stages come spring of next year, Nallet claims there is a positive vibe within the camp. Head coach Pierre Berbizier recruited heavily during the off season but Nallet insists there
is already a family feel amongst the squad.
"There is a good atmosphere in the club," added the 33-year-old French skipper. "There are quite a few new players including myself, and we are already solid as a group. "Everyone expects us to justify the club's promotion at the end of last season, so it is a little tough understandably but, all in all, it's good to be in this new situation and I am very
happy playing in my new club.
"I think our goal this season in the Amlin Challenge Cup is to achieve the same results as in the domestic league. We want to be competitive both in the Top 14 and in the Amlin Challenge Cup and face top European teams."
Progression to the quarter-finals in their first season of European rugby would be a healthy achievement for Berbizier's new charges, with Nallet determined to hunt for success on two fronts. While victory over Montauban last weekend lifted the Parisian-based outfit to ninth position in the Top 14, Nallet knows that a similar result against London Wasps would send a real signal of intent to the other 19 teams searching for Amlin Challenge Cup glory.
"We will do our best to get out of our pool. We have Aviron Bayonnais (Bayonne) that we regularly play in the Top 14 so we know them quite well, but Rugby Roma on the other hand is an unknown quantity and we will have to wait for a few games to be able to analyse them on video. Since we don't play them until Round 3 we will have time to gather information on them and do our homework.
"It's always interesting to play against teams from other countries and it will be a good experience for our club.
"It will be a change from the Top 14 and, although it is a tough competition, the Amlin Challenge Cup gives you a little bit of fresh air and makes you adapt to a lot more different styles of play and that's always beneficial."